TY - Data T1 - Long-term key daily snow parameter dataset for the Three-River Source region from 1970 to 2020 A1 - Zhao Zisheng A1 - Yang Ruimin A1 - Hao Xiaohua A1 - Wang Haidong A1 - Li Hangxuan A1 - Zhong Xinyue A1 - Wu Xiaodong DO - 10.12072/ncdc.db7701.2026 PY - 2026 DA - 2026-09-01 PB - National Cryosphere Desert Data Center AB - This dataset provides daily data on key snow cover parameters from 1970 to 2020. Snow cover parameters include snow cover extent (SCE), snow depth (SD), and snow water equivalent (SWE). The spatial resolution is 5km, and the snow cover period is from 1970 to 2020 (October 1 of the current year to April 30 of the following year). SCE data from 1980 to 2020 uses AVHRR surface reflectance data and Landsat-5TM data, combined with ground snow depth observation data, long-term daily snow depth observations, surface temperature and DEM, and is constructed using improved cloud detection algorithms, multi-level snow cover discrimination algorithms and gap filling strategies; The 1980-2020 snow depth data combines the newly calibrated enhanced resolution brightness temperature to optical snow area ratio and snow cover days. It is retrieved using the deep learning FT-Transformer model and calculated from monthly average snow density. SD is converted into SWE data with a spatial resolution of 5 km. Using LightGBM The (Light Gradient Boosting Machine) model takes snow depth data from 1980 to 2020 as the target variable, combines air temperature, precipitation, wind speed, DEM, slope, sine values of slope direction, cosine values of slope direction and vegetation type, etc., to generate daily SD reconstruction data with 5km spatial resolution from 1970 to 1979; Using the monthly snow density data from 1970 to 1979, SD was transformed into a daily SWE product from 1970 to 1979 with a spatial resolution of 5 km; at the same time, using the snow cover spatial distribution data from 1980 to 2020, the average SD threshold of snow-containing pixels on SD product was determined, snow and snow-free pixels were identified, and the daily 5-kilometer snow cover range product from 1970 to 1979 was completed. DB - NCDC UR - https://www.ncdc.ac.cn/portal/metadata/9bf62a9b-97a0-41e0-9f91-77c728c9dfa6 ER -